C
- (Mayo County) Cross
- (Mayo County) Corratowick
- (Mayo County) Cashel
- (Mayo County) Curry
- (Mayo County) Clonnagh
- (Mayo County) Carn
- (Mayo County) Cloonaghmore
- (Mayo County) Cloonaghduff
- (Mayo County) Cogaula
- (Mayo County) Corrabaun
- (Mayo County) Clooneen
- (Mayo County) Cloghan
- (Mayo County) Clerhaun
- (Mayo County) Carrowbeg
- (Mayo County) Cloonkeen
- (Mayo County) Cloonan
- (Mayo County) Cornaveagh
- (Mayo County) Cottage
- (Mayo County) Cornamarrow
- (Mayo County) Corratanvally
- (Mayo County) Coolnabinnia
- (Mayo County) Contoon
- (Mayo County) Cunnagher North
- (Mayo County) Cloonkesh
- (Mayo County) Cappa
- (Mayo County) Coarsepark
- (Mayo County) Carrownurlaur
- (Mayo County) Cloontybaunan
- (Mayo County) Clooneen
- (Mayo County) Caurans